Inside the tail section of a Twin Commander 680FP

[ghancock]

I took a few videos and compiled for your review.  Here are the highlights:

1) First video you see is the supercharger spinning up in Ground Cool mode.  You hear it spin up and then hear another noise which I'm thinking at the moment is a hose bursting due to too much pressure building up.  I'm starting to think the secondary heat exchanger is causing the problem but just not sure yet.  Morris is sending me a primary supercharger to replace mine to see if it is the problem but hoping these videos can help me narrow in on the problem.

2) You'll notice in the first clip something falling down from the hoses, I'm going to have to go find the piece tomorrow to see what it was and maybe it will be a clue.

3) The other clip is the same scene from a different perspective.

4) The 3rd and 4th clips are after plane has taken off to try to narrow in on another problem.  It is the problem I've mentioned before which is a stutter in the entire airplane that happens all the time.  I've been thinking it might be something in the tail section causing it from the air blowing through the scoop but that doesn't appear to be the case.

To see what I'm talking about though, watch the last clip very closely on the right panel that covers the fuses and electrical box.  You'll notice it being very still and then bouncing as if I hit a bump of air.  Problem is, there was no bump of air.  It just does this constantly as if something on the plane is buffeting, but I haven't been able to figure out what it is.  It is however, driving me insane!!!

https://youtu.be/e1PUJpLVSB8

Glenn

[Davidwheep]

The OP has dropped the same text off on a variety of forums.

Why dont you introduce yourself, Kaichen?

[Bruce Byerly]

Glenn - under what conditions does it vibrate?  Only with the environmental on?  Some kind of compressor stall?  Does it do it at all speeds, is it power related? Have you videod the horizontal in flight?

[ghancock]

Sorry for the late reply as I've been covered up with work.  I actually think I found the problem and it was a bad cylinder on one of the engines.  Since fixing that the vibration has stopped.  The problem with these big engines and props is narrowing in on things like this is quite difficult because the engines are behind you and trying to figure out what is going on is difficult, at least for me.

Thanks,

Glenn